CRUCIFERAE. 



I6 7 



Athysanus, 169. 

 Thysanocaepus, 169. 



Pod orbicular, 1-celled. 



Fruit wingless; pubescence branched. 218. 

 Fruit winged; pubescence simple. 219. 



Pods dehiscent, 2-valved, either elongate (sili- 

 ques) or short (silicles). 

 Pods elongate (siliques). 



Siliques compressed parallel to the broad 

 partition. 

 Valves 1-nerved; cauline leaves ses- 

 sile. 220. Arabis, 169. 

 Valves nerveless; leaves all petioled. 

 Flowers red; stem 2 or 3-leaved at 



or above the middle. 

 Flowers white; stem leafy below or 

 throughout. 

 Siliques terete, not at all compressed. 

 Pods 4 cm. or more long. 



Flowers not yellow; stigmas entire 

 or several-lobed, not 2-lobed. 

 Flowers cream-colored, often 



purple-tinged (in ours). 

 Flowers pink-purple (in ours). 

 Flowers yellow; stigmas 2-Iobed. 

 Flowers large; leaves nearly en- 

 tire. 

 Flowers small; leaves pinnati- 

 fid. 

 Pods less than 4 cm. long. 



Herbage canescent; flowers white. 

 Herbage not canescent; flowers 

 yellow or white. 

 Siliques beaked; seeds globose. 

 Siliques beakless; seeds oblong. 

 Valves of the pods nerve- 

 less. 

 Valves of the pods nerved. 

 Annuals; leaves pin- 

 nate or pinnatifid. 

 Perennials ; leaves ly- 

 rate. 

 Pods short (silicles). 



Silicles compressed parallel to the parti- 

 tion. 

 Silicle turgid. 

 Silicle flat, not turgid. 



Silicles orbicular. 231. 



Silicles ovate or oblong. 232. 



Silicles either not compressed or compress- 

 ed at right angles to the partition. 

 Plant aquatic, submerged; leaves 



subulate. 

 Plant terrestrial; leaves not subulate. 

 Pods terete, not compressed. 



Flowers white; plants mari- 

 time, fleshy. 234. 

 Flowers yellow, or if white the 

 plants not maritime or fleshy. 235. 



221. 

 222. 



223. 

 224. 



225. 

 228. 



226. 



227. 



235. 



228. 

 229. 



Dent aria, 171. 

 Cardamine, 172. 



Thelypodium, 173. 

 Hesperis, 173. 



Erysimum, 173. 

 Sisymbrium, 175. 

 Smelowskia, 174. 



Brassica, 174. 



Radicula, 179. 



SlSYMBRIUM,175. 



Barbarea, 176. 



230. Lesquerella, 176. 



Alyssum, 177. 

 Draba, 177. 



233. Subularia, 178. 



Cochlearia, 178. 

 Radicula, 179. 



